These types of joint-sealing tapes usually consist of polyethylene or polyurethane foam. The spectrum of flexible foams extends from closed-cell foams, which allow virtually no air to pass through, to open-cell foams, which have relatively high air permeability. At least the open-cell foams are usually saturated with an impregnate to achieve the desired sealing properties. Such impregnates also lead to a delayed recovery of the foam after its compression, because the impregnates usually contain adhesive substances, which settle on the cell webs of the foam structure and adhere there. Use is often made of the delayed recovery effect when joints are to be sealed, in that the foam is first compressed and inserted into the joint to be sealed, whereupon the foam partially re-expands to assume its functional state and seals the joint. Usually, such joint-sealing tapes are sold wound up to rolls.
Pasty and injectable sealing compounds of polyurethane, silicone, or acrylate, which are available on the market in many colors, are also used for sealing. Such sealing compounds are hardly usable in expansion joints, however, because they stick to the sides of the joint and can tear if the expansion is too great.
Joint-sealing tapes in the exterior area of buildings are frequently being left uncovered after installation nowadays and are thus being left exposed to the weather, and in some cases they are even visible to observers on the outside.
It is therefore an object of the present invention to create a roll of joint-sealing tape of flexible foam capable of recovering its shape after compression which is also suitable for use in uncovered exterior joints and which creates a superior overall aesthetic impression.